Pneumatically-operated musical instrument



Mar. 1.3, 1923.

M. W. OBERMILLER PNEUMATICALLY OPERATED MUSICAL INSTRUMENT 2 sheets-sheet 1 Filed Aug. 28, 1920 a7 JR/Cke'F O enifi la'l'o,..".

Mar. 13, 1923. 1,448,234 M. w. OBERMILLER PNEUMATIGALLY OPERATED MUSICAL "INSTRUMENT Filed Aug. 28, 1920 2 shee tssheet 2 Q v &

I vi 7 Patented Mar. 13, 1923.

MAXIMILIAN W. OBERMILLER, OF NEW YORK, N. Y.

PNEQMATICALLY-OPERATED MUSICAL INSTRUMENT.

Application filed August 28, 1920.

Z '0 all whom it may concern Be it known that I, MAXIMILIAN IV. OBER- MILLER, a citizen of the United States, and a resident of New York city, county and State of New York, have invented certain new and useful Improvements in Pneumatically- Operated Musical Instruments; and I do hereby declare the following to be a full, clear, and exact description of the invention,

such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

My invention relates to pneumatically operated musical instruments, and more par ticularly to the mechanism controlling the primary or striking pneumatics and the actuator mechanism operated thereby.

I have illustrated the mechanism embodying nip-invention, by way of example, as applied to an upright piano, and the invention comprises a lever operated by the primary pneumatic, which lever operates the piano action either by striking the wippen of the action. or by moving sticker or abstract. I have chosen for the purpose of illustration a well-known type of action where the power is applied to an. extension of the abstract swing. The lever is accessible and adjustable from the front of the piano, thereby rendering the adjustment of each primary pneumatic very easy, without having to remove any parts from the piano.

l\Iy invention also relates to the so-called reproducing pianos, where the expression given to a particular piece of music by a particular performer may be accurately reproduced, and to this end the wind for each primary pneumatic is controlled by a sep arate mechanism, and these mechanisms may be constructed to operate individually or, as customary, in groups, one group for the bass and the other for the treble; and when arranged in groups the control may be automatic or manual or both.

By means of my individual primary pneu matic control I obviate many objections to player pianos and reproducing pianos, namely that after playing a large number of notes, whether loud or soft, there will always be sufiicient wind to sound another number of notes, or a. single note, either soft or loud. That is to say, after either loud Serial No. 406,686.

playing or soft playing there is always sufiicient control to make what is termed a crash to be played under normal pumping.

The difiiculty heretofore has been when the tension on the wind chest has been greatly diminished suddenly, it cannot instantly be brought to normal tension from the reservoir and pumps. This defect is overcome by opening each valve controlling a primary pneumatic to a greater area to the wind in the wind chest.

I also provide a duct by-passing the reservoir, so that the pump may exhaust from the main wind conduit or trunk without having to first pass through the reservoir, thereby causing the proper tension to quickly build up in the wind chest and stack.

Details of invention will be hereinafter described and claimed.

Referring to the drawings, in which like parts are similarly designated Figure 1 is a side elevation, partly in section, showing the stack board and adjustable levers.

Fig. 2 is a front elevation on a smallerscale, partly in section, and illustrating a sufficient number of one group of primary pneumatic control valves.

Fig. 8 is a plan view of a. group of actuating levers at the stack.

Fig. 4 is a section, full size, of a control valve for a primary pneumatic.

F 5 is an elevation thereof.

Fig. 6 is a view similar to Fig. 1, illustrat ing the control of each individual primary pneumatic control valve at the wind chest.

Fig. 7 is a fragmentary elevation, partly in section, of Fig. 6.

Fig. 8 is an elevation of a modification similar to Fig. 5, and

Fig. 9 is a side elevation of one of the valve actuator rods.

Referring now more particularly to Figs. l-.to 5, I have shown in Fig. 1 in side View and in Fig. 2 in front elevation a portion of what is commercially known as a stack containing the mechanisms for action on the piano actions. The stack comprises primarily, a substantially vertical stack board 1, carrying the primary or striking pneumatics 2 and port blocks 9 on one side and the valve units 3 controlling said primary pneumatics on the other side. I shall therefore describe one primary pneumatic and its associated mechanism in detail, it being understood that opening.

the other pneumatics and their associated mechanisms are duplicates thereof for each note on the piano.

I have only shown so much of a piano action as will be necessary to an understanding of the invention, and this comprises the small action rail a that supports the abstract swing 7) that is pivoted to the abstract or sticker 0 provided on its enlarged lower end with felt (Z against which the manual keys strike. This general arrangement is well known in piano actions.

In order to obtain a larger and more ellicient amplitude of movement of the strikinppneumatics I extend the abstract swing; Z) to the front through the abstract and form a rounded head 7' on the end of such extension 6.

The stack board 1 is provided with a pair of transverse or through ports l and for each pneumatic 2, and its control valve 3, that register with a port 6 covered with screen gauze 7 and a port 8 leading to the interior of the pneumatic 2.

These ports '6 and 8 are made in a block 9 that is secured. to'the rear face of the stack board, preferably having inserted between it and the board a thin piece of skin, leather or other packing 10. The ports 6 and 3 are larger than the stack board ports t and 5 to facilitate registration and assembly. The block 9 supports the primary pneumatic by having the stationary wall of the pneumatic secured to the under face of the block against the stack board, and is bevelled on its upperface to prevent the movable wall. of the pneumatic from striking a block i the row of pneumatics next above it.

Each pneumatic 2 is controlled by a valve unit 3, more clearly shown in Fig. 4; com prising three layers of wood or other material, 2 is, Z, assembled to form three chambers 11, 12 and 13, separated by valve seats 1d and 15, with which cooperates a gravity valve 16 guided on a pin 17 in block -23.

The chamber 13 communicates by port 18, the stack board port 4- and block port 6 with the atmosphere. The middle, or valve chamber 12 communicates by a port 19 stack board port 5 and block port 8 with the interior of the pneumatic 2.

Chamber 11 has a port 20 that opens into the wind chest 21 inclosing all the control valve units of the stack. The upper and. lower surfaces of the valve 16 are faced with leather or its equivalent, to insure tight seating on the valve seats 15 and 14-. and said valve has a stem 22 resting on a wear disc 23 on a diaphragm 24-. Through the lower block Z is a bleed bore 25 having inserted at its front the usual brass bleed nipple 2. communication 27 below the diaphragm 2 and connected at its rear end with a stack board passage 28 for connection to a tracker Thevalve unit 3 is faced with skin or leather 29 where itjoins the stack board, and the ports 18 and 19 andbore 25 are preferably larger than the stack board openings with which they register to facilitate assembly and registration. Each valve unit 3 is held to the stack board 1 by screws 30, Fig. 5. and these screws also hold in place a valve plate 31 having preferably a circular offset 32 in which is a thin disc 33 having' approximately a quadrant sector 34: cut out. The valve has a pin or screw 34 passing through the plate 31 and secured in an operating lever so that the lever 35 and valve 33 move as a unit. The offset 32 has a port 36 preferably T-shaped whose enlarged area on has a tapering arcuate extension at.

The upper end of the valve lever 35 is bent outwardly to insure its passage past the heads of the screws 30, should they not be screwed in properly, and this upper end is provided with a slot 37 for the reception of an actuating pin 38, Fig. 4. This pin (one for each valve unit) projectsfrom a rod 39 common to all the units of a row included in the section to be controlled. The port 20 and bleed 26 communicate with the inclosiug wind chest through the T-shaped valve port 36, and the valve 33 is so set that the port 36 is never fully closed under any condition of operation, thereby insuring proper bleeding.

Secured by screws 30 at suitable intervals are guide brackets 40 for the rods 39, one for each row, customarily three. The rods 39 of the several rows are connected together by an end cross head n, Fig. 2, and the central one is connected to a bell-crank lever 42 Fig. 3, urged by a spring 4L3 that normally holds the valves 33 in open position. This bell-crank lever 42 is connected to one end of a rod 44 passing through the front wall of the wind chest 21, suitably packed, as at The other end of this rod is connected to a bellcrank lever 46 whose tail is engaged by the forked end of a rod 47. This rod is pivoted in a bracket 48 attached to the side of the piano case. The rod is flattened at 49 and passing; freely through the flattened portion is an actuating rod 50 having an abutment 51 thereon consisting conveniently of a nut and a locking nut.

The rod 50 is connected to a lever arm 52 on a rod 53 provided with a manual control lever 54- for the bass section. A like lever 54- controls the treble section.

The lower end of lever 47 passes throurl'i a slot in an angle iron 55 on the movable wall of bellows 56 provided with a control valve unit 57 identical in construction with that illustrated in Figs. l and 5 excepting that the valve plate 31 is omitted. This valve unit is provided with a small wind chest 58 and the bleed bore is connected by a tube 59 to a tracker opening.

Th windchest 58' is connected by-a tube 60 to a wind trunk 61 leading, either directly or indirectly, from wind chest 21 to a reservoir 62.

This reservoir is provided with the usual leaf spring 63 and auxiliary coil spring 64 that comes into action only when the reservoir has partly collapsed.

I have shown one of the pumping bellows 65, its spring 66 and valve 67 controlling communication between the bellows and reservoir. In addition to this custom ary pump I provide a by-pass passage 68 in the stationary wall, one end thereof con trolled by the pump valve 67 and the other end connecting directly with the wind trunk where it joins the reservoir, so that, in a measure, the reservoir 62 may be by-passed. This by-pass is of especial advantage in connection with the two spring reservoir and allows the wind in the wind chest to build up quickly with but little effort.

Secured to the rear of the stack board 1, Fig. 1, below the 'rows of primary pneumatics 2 is a pin rail 69 provided with down wardly extending guide pins 70 spaced apart, one for each pneumatic. Corresponding to each pin 70 there is on the front of the stack board 1 abracket 71 held to the board 1 by a screw 72 in which is pivotally suspended at 73 a lever 7 4 extending under the stack board. This lever is guided by a pin 70 and engages the head f of the extension of the abstract swing Z A felt 7 5 is secured to the endof the lever at-the contact point.

Each pneumatic has secured to its movable wall an extension 76, composed of sheet metal, having at one end a lug 77 entering a hole in or driven into the movable wall of the pneumatic and held in place by a screw or nail 78. The lug prevents the extension from rotating on the screw or nail '78. This extension is shaped as shown, and cupped or dished at its other end at 79, and usually has a. slot. Through this dished end extends the threaded end 80 of the lifter rod 31 adjustably secured in place by leather or equivalent nuts 82. The lower end of the lifter rod has a hook 83 passing through the lever 74;, as shown.

At suitable points along the front of the stack board 1 and spaced therefrom by metal tubes 84 is secured a rail 85, and secured to this rail by similar spacing tubes 86 is a like rail 87. In these rails are mounted upper and lower abutments or stops. These stops have rounded heads 88, square necks 89 for the reception of a spanner, and screw shanks 90 that screw into the rails.

Between a pair of stops passes the tail of one of the levers 74 having on its upper and lower faces a felt. The tail of this lever tapers suitably and extends sufiiciently in front of the stops so that it may be conveniently grasped by the fingers for testing the adjustment. The tail of the lever normally rests against the upper stop, while the lower stop is normally spaced therefrom and determines the extent of movement or throw to be allowed to the lever and the pneumatic 2.

I have shown the mechanism assuming the piano to be divided into bass and treble sections, the bellows 56 and connected parts operating all the valves 33 for the bass notes at the'left while a duplicate mechanism op erates the valves 33 for the treble, there being, of course, but one reservoir and pump mechanism, as will be readily understood by those conversant with this type of piano. Anyother sub-division may be made to suit the particular ideas of any piano builder.

It is also to be understood that the piano may be'operated by pressure wind instead of by suction wind by simply changing the construction of the valve units 3, as is well understood by any maker of pneumatically operated pianos.

The operation is as follows: When a bleeder passage is vented to the atmosphere by a tracker port becoming uncovered by the note sheet, the diaphragm 24 lifts valve 16 onto its upper seat 15, thereby closing chamber 12 normally vented through chamber 13, and ports 18, 4 and 6 to the atmosphere, and the interior of the pneumatic 2 is connected by ports 8, 5 and 19, valve chambers 12 and 11 and ports 20 and 36 with the tension in the wind chest 21.

The pneumatic collapses, lifts lever 74, which suddenly lifts the abstract swing and abstract, and causes the note to speak. The intensity and speed with which the neumatic collapses is now controlled by lever 54 for bass, and by 54 for the treble, operated manually by the person playing the instrument. If the note sheet and tracker are provided with control perforations, bellows 56 is caused to collapse. In either instance, or both combined, the lever 47 is swung as indicated by the arrows Fig. 2, thereby operating bell-cranks 46 and 42, as indicated by the arrows Fig. 3, to pull the cross head 41 and rods 39 to the left. The levers will thus be swung to the left, to partly close the ports 36 of the units 3 by rotating the individual unit valves 33.

The reduction of area of a port 36 is quite sudden, as the area m is first closed and thereafter a portion of the arcuate slot n, but nei'er fully.

Thus each valve unit will be under control so that when playing softly under slow pumping with consequent low tension and the valves 33 nearly covering their ports 36, each and every note will be capable of forte speaking when the valves 33 are fully opened, notwithstanding that normal tension does not exist in the wind chest, 21.

The mechanism above described is for loud and soft playing under automatiocontrol, i. 0.. for, two positions of valves 33.

An additional middle, position may readily be obtained by making bellows 56 a double bellows of the type of bellows shown at 91 Fig. 6, there being supplied for its control two control valve units one for each chamber of the double bellows, and each valve unit controlled from a separate tracker opening, as will be readily understood by those familiar with pneumatic. piano construction. 1 i

In Figs. (3 to 9 1 have shown a modification of the control, in which each valve 33 is operated by a multiple or two-chambered pneumatic 91, and each double pneumatic is controlled by two small valve units 92; placed side by side and identical in construction with the valve unit Fig. 4 excepting the plate '31 and valve 33. These double pneumatics 91 and their valve units 92 may be very small as their only function is to operate a single valve 33 that requires but little power. The valve units 92 are enclosed in an auxiliary wind chest 93, similar to the wind chest 21.

Each rod 94 from a double pneumatic is secured to the pneumatic in the manner hereinbefore described and passes through the top ofthe wind chest 21 and connects to the lever 35 of the valve 33. This lever has a perforation 95 and a longitudinal slot 96 passing across the perforation as shown in Fig. 8, thus allowing the split part to readily separate to insert the lifter rod 9%. This rod is bent at right angles at 97, where it passes through the perforation and has a small head 98 to prevent it from working out of the perforation.

A construction such as shown in the modification requires a large number of contral openings in-the tracker and note sheet, two for each auxiliary pneumatic 91, and the tracker if constructed in the usual mannor will have to be at least of double width with a corresponding width of note sheet.

A reproducing piano having such a mechanism permits each and every note to be automatically controlled in three intensities,loud with full open port 36, medium when portion m is closed, and soft when portion a is partly closed.

The reproduction can, therefore, be as accurate as possible, and the individual. expression of the artist making the original record can be reproduced automatically with extreme .exactitude.

By having all the valve units 3 on the front of the stack board, they can be removed, and replaced by new ones without disassembling the piano, and the adjustment of the touch can also be effected from the front of the piano by adjusting the stops in rails 85 and 87.

I claim-- 1. A pneumatic valve unit, comprising three chambers, a valve in the middle chan'iber and .a diaphragm in one of the other chambers, the third chamber ported to the atmosphere, the middle chamber ported to a pneumatic, and the diaphragm chamber ported to operating'wind, a tracker connected bleeder passage communicating below the diaphragm and bleeding to operating wind, and a valve simultaneously controlling the operating wind to said bleeder passage and said diaphragm chamber.

2. A control device for valve units for primary pneumatics, comprising a plate for covering the openings of said unit using operating wind, said plate having a port therein and a rotatable valve controlling said port.

The combination with primary pneumatics and a control valve unit for each pneumatic, of a separate valve for each unit controlling the tension to each control valve, and a wind chest inc-losing said control valve units and their separate valves.

4L. A control device for valve units for primary pneumatics, comprising a plate hav ing a circular offset portion, a port in said offset portion, a disc valve in said olfset portion controlling said port, and an operating lever connected to said valve.

5. A control device for valve units for primary pneumatics, comprising a plate having a T-shaped port therein and a rotatable valve controlling said port, said valve arranged to control operating wind to said unit and its bleed.

6. A. control device for valve units for primary pneumatics, comprising a plate having a port having a sector shaped portion and an arcuate portion extending there from, and a rotatable disc having a sectorshaped cut out portion and controlling said port. i

7. A control device for valve units for primary pneumatics, comprising a plate having a port therein large at its initial end diminishing toward its closing end.

8. The combination with a valve unit for primary pneumatics, of a valve connected to said unit for simultaneously controlling the operating wind to the unit and its bleed.

9. In a pneumatically operated piano, primary pneumatics, a control valve for each pneumatic, a valve for each control valve for controlling the operating wind. to each unit and its bleed.

10fIn a pneumatically operated piano, primary pneumatics, a control valve for each pneumatic, a valve for each control valve for controlling the operating wind to each unit and its bleed, and pneumatic mechanism to operate the wind control valves in groups.

11, In a pneumatically operated piano, primary neumatics, a control valve for each pneumatic, a valve for each control valx e for controlling the operating wind to each unit and its bleed, pneumatic mechanism, and manually operated mechanism to operate the Wind control valves in groups.

12. The combination with a primary pneumatic and itscontrol valve unit and a wind chest enclosing said control valve; of a throttle valve to control the operating wind from said chest to said unit, and a pneumatic and its control valve unit for opcrating said throttle valve.

MAXIMILIAN W. OBERMILLER. 

